From Diablo Wiki
A Binding Stone is a magically infused stone used to hold something. Only one is known to have been made in the history of Sanctuary, and that's the Binding Stone that Tyrael helped the Horadrim to make, which held Tal Rasha in place for decades, imprisoning Baal within his own soul.
- Main article: Tal Rasha
The Binding Stone was made by the Horadrim and inscribed with magical runes indecipherable by mortal men after Baal was defeated. The mage Tal Rasha was bound to it with magical chains and had the Soulstone of Baal thrust inside his flesh.
About Binding Stone(s)
A Binding Stone is either just a magical stone to keep something or someone in place, or could possibly even be a makeshift Soulstone created with the limited materials available on the mortal plane. It's clear it can bind other things than Prime Evils, however, as Tyrael was bound to it by Baal and the Wanderer after he failed to stop the demon being freed.
If they can be corrupted like Soulstones is unknown, and if it's even possible to move it or permanently destroy it.
Most details of The Binding Stone, or Binding Stones in general are unknown to us.